小儿慢性丙型肝炎外周血T细胞亚群和TH1／TH2型细胞因子的研究

Peripheral blood T cell subsets and TH1/TH2 cytokines secretion in children with chronic hepatitis C virus infection

目的 通过研究小儿慢性丙型肝炎外周血T细胞亚群及TH1／TH2型细胞因子的表达，进一步探讨小儿慢性丙型肝炎的免疫发病机制。方法 （1）流式细胞仪（FACS）检测16例慢性丙型肝炎患儿及10例正常对照外周血T细胞亚群。（2）将慢性丙型肝炎患儿和正常对照外周血单个核细胞（PBMC）体外培养72h后，用ELISA法检测培养上清中TH1型细胞因子（IFN-γ、IL-2、IL-12和TNF-γ）和TH2型细胞因子（IL-4、IL-10）的浓度。结果 （1）CD4^＋细胞无明显变化。CD8^＋细胞与正常对照比较明显升高（P〈0．05）。CD3^＋细胞升高，CD4^＋／CD8^＋比值下降，但与正常对照比较无统计学意义（P〉0．05）。（2）PBMC培养上清中IFN-γ、IL-10和TNF-α的水平明显升高（P〈0．01），而没有检测到IL-2、IL-4、IL-12的基础分泌。结论 慢性丙型肝炎患儿体内T淋巴细胞存在数量和功能的异常，CD8^＋细胞数升高，CD4^＋细胞功能异常，表现在以TH2型细胞因子的分泌为主。这可能与丙肝病毒（HCV）感染的慢性化有关。

Objective To determine the cellular immunological abnormalities in children with chronic hepatitis C virus infection. Methods （1）The quantity of the peripheral blood T cell subsets in 16 children with chronic hepatitis C virus infection and 10 healthy blood donors was detected by FACS. （2）The levels of the TH1/ TH2 cytokines secretion of PBMC in patients and healthy blood donors were detected by ELISA. Results （ 1 ） Compared with normal controls,there was no significant difference in the percentage of CD4^＋ cells. The percentage of CD8^＋ cells was significantly higher than that of controls（ P 〈 0.05）. The percentage of CD3^＋ cells was higher and the ratio of CD4^＋/CD8^＋ cells was lower, but the difference was not significant（ P 〉 0.05 ）. （2） Compared with the cytokine level of normal control, the levels of IFN-γ, IL-10 and TNF-α notably increased （P 〈 0.01 ）while IL- 2,IL-4,and IL-12 were not detected in the culture supematant of PBMCs from both normal control and patients. Conclusion There is an imbalance in peripheral blood T cell subsets and disturbance in cellular immunity in children with chronic hepatitis C virus infection, which may be associated with HCV persistent infection.